QCHAT is a cluster communication technology based on a mobile network, which may provide functions such as single call, group call, emergency call, broadcast call, and call priority. QCHAT supports one-to-one and one-to-many half-duplex radio voice communication, and is a solution to cluster communication on a third generation mobile communication network. Its features lie in that: response is quick (call establishment time is shorter than 1 second (s)), efficiency is high, stability and reliability are desirable, and a half-duplex mechanism is adopted, that is, at the same time, only one person has the right to speak and can speak.
However, in a process of implementing the present invention, the inventor finds that the prior art has at least the following problems:
A QCHAT service is implemented based on a packet data service, and therefore, a mobile terminal that has a QCHAT function (especially, a QCHAT mobile phone) needs to perform data update during start-up. Certain traffic expense is incurred when obtaining information such as group information and configuration data from a network is completed during the data update, which means a unified tariff for a QCHAT user, and this part of traffic affects a user tariff slightly. However, for a common user (a user that uses a QCHAT mobile terminal, but a QCHAT service is not activated in an inserted mobile terminal card), the following problems exist: the mobile terminal may still apply to the network for updating relevant group data in a start-up process, and in a whole procedure, charging is started after packet data serving node (PDSN) authentication succeeds. At this time, the mobile terminal requests for data update. However, because a QCHAT service is not activated in a current mobile terminal card, a QCHAT server refuses an update request, but traffic expense is incurred in this procedure. Especially, in a place where no QCHAT server is deployed, the mobile terminal keeps sending a request after the request expires. If the number of requesting times is greater than 10, more traffic expense is incurred and more time is occupied. The foregoing traffic expense is incurred during each time of start-up for a common user, and start-up and shutting-down are frequent operations of the user. Therefore, an existing QCHAT mobile terminal incurs a large number of invalid tariffs to the common user.